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1.
目前,因食品安全、生活习惯、社会压力等问题,我国女性乳腺癌患者日益增多,并逐渐发展为女性最常见的恶性肿瘤之一。前期对乳腺癌进行调查研究后发现乳腺癌的诊断对后期临床治疗的选择具有极其重要的影响。超声成像技术是截止目前最有效的诊断乳腺癌方法,本文主要研究了二维超声成像技术、三维超声成像技术及二维联合三维超声技术使用在乳腺癌中的应用价值,并对此技术的前景进行展望。  相似文献   

2.
目的评价经直肠前列腺超声造影参数成像对临床怀疑前列腺癌但超声没有发现明确病灶患者前列腺癌预测的临床应用价值。方法对30名血清PSA升高而灰阶超声没有发现明确病灶的患者在同天先后行经直肠前列腺超声造影及经直肠超声引导下前列腺穿刺活检的操作。造影图像切面选择在前列腺底部、中部及尖部与穿刺部位保持在同一切面,超声造影及穿刺活检由同一名医师承担。采用SonoProstate软件进行参数成像并分析造影参数图像。统计分析参数图像结果与病理结果。结果19例病理证实为前列腺癌的病例中参数成像方法诊断15例,11例病理证实为前列腺增生的病例中参数成像方法诊断9例。前列腺超声造影参数成像与超声引导下前列腺穿刺活检术对前列腺癌的预测无统计学差异(P=0.687)。结论对血清PSA升高但灰阶超声未发现明确前列腺病灶的患者,经直肠前列腺超声造影参数成像有助于提示前列腺癌可疑部位并指导前列腺穿刺活检。  相似文献   

3.
目的:探讨经阴道二维彩色多普勒超声与血清孕酮联合检测对先兆流产预后判断的价值。方法随机选取孕5—8周早孕患者138例,其中正常宫内早孕(A)组46例,早期先兆流产92例(B),分别行经阴道彩色多普勒超声检测子宫螺旋动脉、黄体血流的RI、H值及化学发光法检测血清孕酮水平,随访先兆流产者至16周孕,继续妊娠者视为保胎成功归入B1组,反之则归入B2组,比较其各组间的差异并研究各指标单检及联合检测对预后判断的价值。结果:子宫螺旋动脉RI、PI值,黄体血流RI、PI值及血清孕酮值在A、B组间差异有统计学意义(P〈0.05);其中子宫螺旋动脉m、黄体血流砌及血清孕酮值在B组内(B1与B2组间)差异有统计学意义(P〈0.05)。子宫螺旋动脉RI、黄体血流血及孕酮三者联合检测对先兆流产预后判断的准确性、特异性及阳性预测值分别为85.9%、89.8%、81.3%,较各指标单检及两联检测均高,差异有统计学意义(P〈0.05)。结论:血清孕酮联合彩色多普勒超声检测子宫螺旋动脉RI及黄体血流血能够明显提高先兆流产预后判断的准确性、特异性及阳性预测值,对准确判断先兆流产预后具有重要临床意义。  相似文献   

4.
目的:研究阴道超声发现子宫内膜异常患者的宫腔镜诊治价值。方法:对827例经阴道超声检查发现子宫内膜异常的患者行官腔镜检查,并行诊断性刮宫或宫腔内病变电切,组织物送病检。结果:以病检结果为诊断标准,宫腔镜检查对子宫内膜息肉、子宫粘膜下肌瘤、正常子宫内膜、宫颈管息肉及子宫内膜癌的诊断符合率均明显高于阴道超声检查(P〈0.01);宫腔镜检查对子宫内膜病变诊断的敏感性和特异性分别是95.23%和86,82%,而阴道超声检查对子宫内膜病变诊断的敏感性和特异性分别是83.99%和41.23%。结论:对阴道超声检查发现子宫内膜异常的患者应常规行宫腔镜检查并取组织活检,才能提高诊断符合率,减少误诊和漏诊。  相似文献   

5.
为实现非接触式三维超声反射成像,搭建了基于16×4阵元电容式微机械超声换能器(CMUT)面阵的反射成像系统。利用面阵上单个阵元发射、所有阵元接收的方式对硅油中的铝块进行了三维成像测试。采用B模式及二次谐波两种成像算法分别对来自铝块的反射信号进行处理,获取被测物的三维图像及对应的二维切片。基于16×4阵元CMUT面阵的反射成像系统能够确定铝块的位置,实验B模式图像和二次谐波图像中铝块与换能器的距离重建偏差分别为3.63%及1.47%。该系统可实现对被测物的三维反射成像,且三维反射图像中被测铝块的表面清晰可见,重建偏差小,信噪比高。  相似文献   

6.
随着现代工业的发展,由于传统的二维超声成像检测反映的缺陷空间信息过于片面,已经不满足实际的检测需求。因此,超声三维成像检测技术应运而生。超声三维成像技术包括丰富的缺陷空间信息,对工件的无损评价有实质性的帮助。该研究借助可视化工具包(VTK)绘制平台,采用编码器触发的一维线阵换能器对工件进行全覆盖式扫查,将每个截面的相控阵线阵换能器扫查所得的A扫波形信号进行横向排列处理,绘制出各个截面的B扫图像。提出了最临近插值绘制法,将各个截面的B扫图像进行堆叠,重构工件的三维图像。通过对试块的三维成像结果表明,该成像方法能准确地反映缺陷的空间信息。  相似文献   

7.
目的 回顾性分析静脉内平滑肌瘤病(IVL)的超声表现,提高对IVL的认识和诊断水平.方法 回顾性分析7例经手术病理证实确诊为IVL临床资料,总结所累及脏器的超声表现.结果 7例均为女性,6例有子宫肌瘤病史,5例已行子宫切除手术,1例超声见子宫肌壁间多发结节及盆腔多发肿物.7例血管彩色多普勒超声均发现一侧髂内静脉伴髂外静脉或髂总静脉占位,并见下腔静脉不同段实性中等回声占位:4例累及下腔静脉下段;3例累及下腔静脉全程,其中2例向上延伸至右心房.结论 IVL的临床表现复杂多样,超声表现有一定的特点,掌握IVL超声特点有助于提高诊断正确率.  相似文献   

8.
目的:探讨超声在人工流产术后的应用价值。方法:分析739例人工流产患者术后不同时期超声检查结果,及其与临床的关系。结果:739例患者中人工流产完全者721例(其中子宫内膜生长良好者678例、子宫内膜生长迟缓者31例、引起宫腔及宫颈粘连者11例、术后感染者1例),人流不全者18例,超声诊断符合率达100%。结论:人工流产...  相似文献   

9.
目的:探讨彩色多普勒超声对胎盘滞留的诊断及治疗价值。方法:分析45例胎盘滞留患者初步临床诊断、初步临床诊断联合彩色多普勒超声诊断与最终诊断的符合情况。结果:初步临床诊断联合彩色多普勒超声对胎盘嵌顿及胎盘粘连诊断与最终诊断的符合率明显高于初步临床诊断与最终诊断的符合率(P〈0.05),对胎盘粘连的漏诊率明显低于初步临床诊断(P〈0.05)。结论:彩色多普勒超声可提高临床对胎盘嵌顿及胎盘粘连诊断的准确率,减少胎盘粘连的漏诊率,并可指导临床处理。  相似文献   

10.
针对空间高速自旋目标的ISAR成像问题,在分析高速自旋目标回波模型的基础上,提出了基于轨道运动的二维成像方法,利用压缩感知思想,有效缩短了成像积累时间,并结合自旋对目标回波的影响,提出了一种三维成像方法。所提方法根据利用轨道信息获得的二维像序列,获取目标散射点沿旋转轴方向的高度维信息,然后利用自旋信息通过压缩感知方法进行二维投影切片成像,从而得到三维成像结果。该方法通过预先获得目标散射点的高度维信息,大大缩减了搜索区间,提高了搜索精度,仿真结果验证了所提方法的有效性。  相似文献   

11.
三维超声成像能提供直观和真实感的组织信息,便于医生对医学体进行观察和分析,已广泛应用于疾病诊断、手术规划和导航中。针对现有超声技术在采集速度和图像质量上的不足,该文采用一种新型的多角度平面波技术获得超声回波信号,并通过USB3.0高速端口传输到PC端,然后进行平面波相干合成、对数压缩、超声序列存储及三维重建等操作,搭建了实验平台并进行测试,研究表明该文方法具有采集速度高,成像效果好的优势。  相似文献   

12.
Spiculation is a stellate distortion caused by the intrusion of breast cancer into surrounding tissue. Its existence is an important clue to characterizing malignant tumors. Many successful mammographic methods have been proposed to detect tumors with spiculation. Traditional two-dimensional (2-D) ultrasound cannot easily find spiculations because spiculations normally appear parallel to the surface of the skin. Recently, three-dimensional (3-D) ultrasound has been gradually used in clinical applications and it has been proven to be useful in determining the architectural distortion or spiculation that surrounds a breast tumor. This paper aims to identify spiculation from 3-D ultrasonic volume data of a tumor found by a physician. In the proposed method, each coronal slice of volume data is successively extracted and then analyzed as a 2-D ultrasound image by the proposed spiculation detection method. First, in each horizontal slice, the modified rotating structuring element (ROSE) operation is used to find the central region in which spiculation lines converge. Second, the stick algorithm is used to estimate the direction of the edge of each pixel around the central region. A pixel whose edge points toward the central region is marked as a potential spiculation. Finally, the marked pixels are collected around the central region and their distribution is analyzed to determine whether spiculation is present. The 3-D test datasets were obtained using the Voluson 530 or 730, Kretztechnik, Austria. First, the proposed method was tested on 104 2-D typical coronal images (selected by an experienced physician) extracted from 52 3-D ultrasonic datasets. Finally, 225 3-D pathologically proven datasets were tested to evaluate the performance. Spiculations are more easily observed in the coronal view than in the other two views. That is, the 3-D ultrasound is a powerful tool for identifying spiculations. Furthermore, 16% (19/120) of benign cases and 90% (94/105) of malignant cases are detected as spiculations.  相似文献   

13.
对超声换能器声场进行三维模拟及可视化的研究,基于MATLAB强大的图形图像可视化功能显示出超声声场的三维图形,通过改变相应参数更直观的观察声场的变化了解影响声场的变化的因素;为超声成像以及超声检测等工程实际问题中超声波的研究以及超声探头的选取提供相应的依据。  相似文献   

14.
Ultrasonic imaging is the noninvasive clinical imaging modality of choice for diagnosing heart disease. At present, two-dimensional ultrasonic grayscale images provide a relatively cheap, fast, bedside method to study the morphology of the heart. Several methods have been proposed to assess myocardial function. These have been based on either grayscale or motion (velocity) information measured in real-time. However, the quantitative assessment of regional myocardial function remains an important goal in clinical cardiology. To do this, ultrasonic strain and strain-rate imaging have been introduced. In the clinical setting, these techniques currently only allow one component of the true three-dimensional deformation to be measured. Clinical, multidimensional strain (rate) information can currently thus only be obtained by combining data acquired using different transducer positions. Nevertheless, given the appropriate postprocessing, the clinical value of these techniques has already been shown. Moreover, multidimensional strain and strain-rate estimation of the heart in vivo by means of a single ultrasound acquisition has been shown to be feasible. In this paper, the new techniques of ultrasonic strain rate and strain imaging of the heart are reviewed in terms of definitions, data acquisition, strain-rate estimation, postprocessing, and parameter extraction. Their clinical validation and relevance will be discussed using clinical examples on relevant cardiac pathology. Based on these examples, suggestions are made for future developments of these techniques.  相似文献   

15.
An ultrasonic reflection-mode CT method was applied to transskull imaging of brain. The method involves only a single transducer and a single scan to acquire data from the object. In reconstruction an ordinary Fourier slice theorem is applied. The average velocity changes of ultrasound due to the skullbone can be compensated. In experiments the object immersed in water was scanned by a wide-angle transducer through the viewing angle of 360 degrees. When imaging through bone a simplified approach was employed in which a piece of skullbone (thickness 3-4 mm) was attached firmly to the transducer. For comparison, the same object was then imaged without the skullbone. A two-point resolution better than 3 mm was achieved for transskull imaging using 1 MHz ultrasound. The experiments with brain specimens show that transskull images compare well with the images of the same specimens obtained without the bone interference. The findings are clinically significant in terms of pediatric brain diagnosis and postoperative follow up. Based on the method, a clinical prototype imager is currently being developed especially for diagnosis of children's brain diseases.  相似文献   

16.
相移迁移法在激光超声合成孔径聚焦技术中的应用   总被引:1,自引:0,他引:1  
通过分析脉冲源激光辐照于工件表面激发的多模式、宽带超声体波信号并结合合成孔径聚焦技术(SAFT),实现了对工件内部微小缺陷的检测、定位和成像。首先基于有限元仿真模拟了激光激发超声波在含缺陷样品中的传播过程,编写了基于相移迁移法(PSM)的SAFT成像算法,然后在实验中使用激光在含缺陷样品表面激发超声波,使用激光测振仪探测超声波,并基于已有算法和探测结果对样品内缺陷进行了检测和定位,以验证算法的正确性。有限元仿真以及实验结果均表明,将激光超声技术与频域SAFT-PSM结合,能够有效地对微小缺陷进行检测和定位,且其图像重构速度快于时域SAFT,可为激光超声无损检测提供更快速的实时技术方案。  相似文献   

17.
The authors explore the application of volume rendering in medical ultrasonic imaging. Several volume rendering methods have been developed for X-ray computed tomography (X-CT), magnetic resonance imaging (MRI) and positron emission tomography (PET). Limited research has been done on applications of volume rendering techniques in medical ultrasound imaging because of a general lack of adequate equipment for 3D acquisitions. Severe noise sources and other limitations in the imaging system make volume rendering of ultrasonic data a challenge compared to rendering of MRI and X-CT data. Rendering algorithms that rely on an initial classification of the data into different tissue categories have been developed for high quality X-CT and MR-data. So far, there is a lack of general and reliable methods for tissue classification in ultrasonic imaging. The authors focus on volume rendering methods which are not dependent on any classification into different tissue categories. Instead, features are extracted from the original 3D data-set, and projected onto the view plane. The authors found that some of these methods may give clinically useful information which is very difficult to get from ordinary 2D ultrasonic images, and in some cases renderings with very fine structural details. The authors have applied the methods to 3D ultrasound images from fetal examinations. The methods are now in use as clinical tools at the National Center of Fetal Medicine in Trondheim, Norway.  相似文献   

18.
临床上常规的超声成像对甲状腺结节进行诊断时存在误诊和漏诊。研究了利用多种采集频率的长焦区聚焦换能器进行光声成像的方法。在模拟样品里埋入不同尺寸的血块模拟病变组织,采用不同中心频率的换能器对模拟样品进行光声成像,然后将血液注入正常人体甲状腺内部形成两处瘀血区,模拟病变甲状腺组织,经二维扫描重构出模拟病变甲状腺组织的三维光声图像。结果表明,不同频率的超声换能器对不同尺寸病灶体的探测灵敏度存在较大差异,5MHz的宽带换能器对几百微米直至毫米量级大小的病灶体均具有良好的灵敏度。获得了甲状腺及其内部两处瘀血区域的较高分辨率和对比度的三维图像。此项技术有望与超声成像技术结合,进一步提高甲状腺疾病诊断的准确率。  相似文献   

19.
设计并制作了一种用于强酸性输液系统除垢的超声波换能器。利用聚丙烯管道组装的静态流体超声场强测试系统研究了影响超声传播的因素。结果表明,使用陶瓷超声发射头有利于超声能量向液相传输,随导波棒粗端与陶瓷发射头接触面积增大,超声波能量传输效率提高。结合有限元分析软件确定了换能器的振动节点,优化换能器结构设计。在硫酸、盐酸、硝酸和氢氟酸酸体系中测试了换能器陶瓷超声头的耐酸腐蚀性能。实验结果显示,主晶相w(Al2O3)>75%、碱金属和碱土金属氧化物总含量小于5%的氧化铝陶瓷超声发射头可以耐受酸度为1.0mol/L硫酸的腐蚀。w(Al2O3)>99%的刚玉陶瓷可用抵御0.5mol/L氢氟酸、或大于1mol/L硫酸的腐蚀。用主晶相w(Al2O3)>75%的氧化铝陶瓷超声发射头,在模拟某锌业公司的实际生产的酸性体系中测试3个月,超声发射头无明显腐蚀。  相似文献   

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